1. Field of the Invention
The subject invention is generally related to emergency telephone systems and is specifically directed to an emergency telephone system capable of being connected to and integrated with a network supported comprehensive multi-media surveillance system.
2. Discussion of the Prior Art
It is common practice to provide emergency telephones in strategic locations such as elevators, along highways and in various facilities such as airports, schools and hospitals. Typically these telephones are pre-programmed to dial a security or response station and automatically dial upon removal of the handset from the switch-hook or cradle. Most of these telephones are “Plain Old Telephone Service (POTS)” devices and are hard-wired to the landline telephone system and rely on a common carrier to transmit the call. In some cases, closed circuit systems or dedicated point-to-point systems sometimes called “ring-down circuits” may be utilized. More recently, some emergency telephones have been installed utilizing wireless telephone technology such as cellular. Solar power of these installations allows for easy installation without relying on other public services such as telephone lines and power lines. These are appearing along remote highways, on college campuses, in parks, and in other outdoor public areas.
In use, the caller requiring emergency assistance will pick up the telephone and once answered, will provide the responding party with details of the emergency. In more sophisticated installations the identification of the emergency telephone will be conveyed utilizing Caller ID (CLID) technology, which then can index into a database and present the location of the telephone from which the call is being made. While these systems have been in wide use for many years, there remain several drawbacks to the usefulness of the system in dealing with many emergency situations. First, the receiving station must be continuously manned in a specific location such as at a guard station. There are many instances where a guard or other personnel is busy making rounds or with other duties and is not available to answer the call immediately upon transmission. In certain types of situations, time may be a very critical factor in dealing with the emergency, and such delays in response can diminish the opportunity to deal with the emergency in the most effective manner.
Further, such systems do not permit the responding personnel to make any personal direct assessment of the emergency. They are required to take the information given to them as accurate and accordingly develop their response. This presents a problem in determining whether the caller is overstating or understating the emergency conditions. This problem is magnified by the fact that the caller may be under some stress when placing the call and may not be able to give accurate information in a calm manner, leaving it to the response personnel to make an assessment of the situation with less than optimum information. In extreme cases, the person making the call may be injured or even incapacitated and not be able to make adequate disclosure of the emergency. The person may also be forced to flee the location of the emergency telephone before a complete disclosure has been made.
Recently, security systems have been developed which have the capability of better assessing an event and of transmitting information to a hierarchy of recipients depending on the assessed conditions. In additions, such systems have back-up capability so that when the first response destination is not available the information is forwarded to back-up response destinations in a selected priority, assuring that a response can be made in a timely manner. An example of such a system is shown and described in my copending applications Ser. No. 09/257,720, filed on Feb. 25, 1999; Ser. No. 09/594,041, filed on Jun. 14, 2000; and Ser. No. 09/853,274, filed on May 11, 2001.
Such systems greatly enhance the assessment of a situation and expedite appropriate responses. To date, emergency telephone systems have not been able to assure the quick and accurate responses that are available with the comprehensive, multimedia surveillance systems such as described in the aforementioned application.
An additional disadvantage is the reliance on landline telephone systems to transmit the call. Often this form of communication is one of the first systems to break down in an emergency. Alternative and back-up communications systems are desired to assure that an emergency call can be properly transmitted to the intended recipient.
More recently, appliances have been designed that permit analog telephone systems to provide voice data that can be converted to IP protocols, permitting digitizing of the information for transmission over digital systems such as LANS, WANS and the Internet. An example of such an appliance is the MULTIVOIP Standalone voice/IP gateway appliance offered by MultiTech Systems of Mounds View, Minn. This system supports analog voice and fax communication of an IP network. These voice over IP or VOIP systems permit standard, analog telephones (sometimes called by the industry POTS—Plain Old Telephone Service telephones) to be used to communicate voice transmissions directly over a digital network system. Cisco Systems also makes a similar product, the ATA 186 Analog Telephone Adapter that allows POTS telephone instruments to perform on an IP telephone system.
Purely digital IP telephones have also been designed. These devices do not convert existing analog telephone instruments to IP; instead they are devices that include the telephone handset, the analog to digital/digital to analog converter (CODEC) and the IP interface into one device. These devices also facilitate transmission of voice over digital networks such as LANS, WANS, Wireless LANS and the Internet. Cisco Systems manufactures two such IP telephones. The Cisco 12 SP+ model is the Cisco IP telephone designed for business professionals and office workers. This voice instrument supports 12 programmable line and feature buttons, an internal, high-quality two-way speakerphone, and microphone mute. This phone also features a large LCD display for call status and identification. An LED associated with each of the 12 feature and line buttons provides feature and line status. The Cisco 30 VIP model is the full-featured Cisco IP telephone for executives and managers. This voice instrument provides 30 programmable line and feature buttons, an internal, high-quality, two-way speakerphone with microphone mute, and a transfer feature button. A large 40-character LCD display features ⅝″ characters provides information such as date and time, calling party name, calling party number, and digits dialed. An LED associated with each of the 30 feature and line buttons provides feature and line status.
Each model, including the analog telephone adapter with a POTS telephone attached, is a full-featured telephone that can be plugged directly into a standard 10BaseT Ethernet connection. Each provides toll-quality audio, with no need for a companion PC. Because they are IP-based telephones, they can be installed anywhere on a corporate IP network. The telephones are connected to typical network switched hubs and routers in a like manner to PC's. In a preferred implementation, the phones and analog telephone adapters are DHCP Dynamic Host Configuration Protocol (DHCP) supported and do not need to be co-located with the IP switch. Typically the analog telephone adapters and IP telephones communicated with digitized compressed voice conforming to a standard such as the popular G.711 and G.723.1 audio compression for low-bandwidth requirements.
Advanced functions are also provided by the more sophisticated IP telephones. In the case of the Cisco IP Telephones, each model also contains an integrated Ethernet repeater, so you can use a single Ethernet switch port for the computer (data) and the IP telephone. Cisco IP telephones are also Microsoft NetMeeting(TM) enabled. Using NetMeeting, features such as application sharing and videoconferencing are available simply by pressing a button on your Cisco IP telephone. The phones are configured using your Web browser.
It is important to note that the switching function in an IP telephony system is provided by one or more computer processing element(s) on the network to which the IP telephones/adapters are attached. That processing element typically contains a plurality of System Processing Engine (SPE) cards. An SPE card is a computing platform that runs the telephony applications that support the IP phones. The number of cards that are required is dependent upon the number of stations that are to be supported. The processing elements can provide a range of telephony applications. Currently they include:                Call Manager Application—an application that provides connection and management of the voice calls. This software maps directories entries and telephone numbers to telephone sets. This includes all of the logic necessary to “route” the data from the IP address of the origination telephone to the correct IP address for the destination telephones.        Conference Bridge Application—this function allows three or more IP telephones and/or adapters to be connected in a virtual conference. This requires mixing or adding of the voice information in the digital domain and the conference bridge application.        Media Transfer Point Application—this function allows connection of calls over a wide variety of circuits. These may be traditional telephony circuits such as ISDN, T-1, T-2, OC-3, etc. They also may be IP circuits. An example of an IP transfer application is the Cisco IP Transfer Point (ITP), a product for transporting Signaling System 7 (SS7) traffic over IP (SS7oIP) networks.        Integrated Voice Mail Application—this application allows the digital streams of voice coming from the IP telephones, analog adapters, and incoming circuit trunks to be recorded in digital format on a System Processing Element or a designated File Server. Access to the server can be made utilizing this application to access the stored digital voice information over the IP network. Access can also be accomplished from the IP telephones, analog adapters, and incoming circuit trunks.        